In a nutshell, the track data has "validated" what I had calculated the downforce would be at 140mph, which turned out to be roughly a delta of 765. The only gap in my testing is that I was only able to do 15 data points, compared to the normal 35-40. Also, at the first day it was quite windy with scattered showers and I noticed a bit too much turbulence to be confident in the readings.